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Solve for x: −3|2x + 6| = −12 (1 point)

User Sylwek
by
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1 Answer

2 votes

Answer:

x = - 5, x = - 1

Explanation:

Given

- 3 | 2x + 6 | = - 12 ( divide both sides by - 3 )

| 2x + 6 | = 4

The absolute value always returns a positive value, but the expression inside can be positive or negative, that is

2x + 6 = 4 ( subtract 6 from both sides )

2x = - 2 ( divide both sides by 2 )

x = - 1

OR

- (2x + 6) = 4 ← distribute left side

- 2x - 6 = 4 ( add 6 to both sides )

- 2x = 10 ( divide both sides by - 2 )

x = - 5

As a check

Substitute these values into the left side of the equation and if equal to the right side then they are the solutions.

x = - 1 → - 3| - 2 + 6 | = - 3 | 4 | = - 3 × 4 = - 12 ← True

x = - 5 → - 3 | - 10 + 6 | = - 3 | - 4 | = - 3 × 4 = - 12 ← True

Thus x = - 5 and x = - 1 are the solutions

User Gras Double
by
4.7k points